Full-Scale Tests on Horizontal Joints of Large Panel Precast Concrete Buildings

Abstract

S ince the 1968 progressive collapse failure of a precast concrete apartment tower at Ronan Point, England,' much attention has been given to the implementation of specific code regulations governing the construction of large panel precast concrete buildings. Many studies'' have arrived at the conclusion that the horizontal joint is the weakest link in this type of construction. The problem arises from the fact that, unlike cast-in-place concrete structures, a non-monolithic construction results from connecting precast panels at the site to form various joints. On the other hand, the reduction in time, labor and hence cost, resulting from factory controlled mass production of large panel structural components is a major factor in their steadily increasing use in residential construction. The large panel building consists basically of precast wall panels with floors and roofs of precast elements or slabs that are usually hollow and prestressed, with the walls and slabs transferring the loads directly to the foundation without intermediate frames. In some cases, the strength and safety of such structures will depend on the connections between the various precast components. The purpose of the connection is to transfer efficiently the internal forces from one element to another. Thus, the strength of adjoining elements can be fully utilized only if the efficiency of the connection, in terms of strength and ductility, is very high. Tests on horizontal joints under increasing gravity loads have been conducted in Poland,2,8,9 France,,11 and the Soviet Union. 12- These results are, however, for joint geometries and